Carborundum articles and process of making same.



UNITED STAT S PATENT OFFICE.

FRANK J. TONE, OF NIAGARA FALLS, NEW YORK, ASSIGNOR TO THE OARBORUNDUMCOMPANY, OF NIAGARA FALLS, NEW YORK, A CORPORATION OF PENNSYLVANIA.

CARBORUNDUM ARTICLES AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 709,808, datedSeptember 23, 1902.

Application filed January 2,1901. Serial No. 41.893. (No specimens.)

To all whom, it may concern:

Be it known that I, FRANK J. TONE, of Niagara Falls, Niagara county, NewYork, have invented a new and useful Improvement in Oarborundum Articlesand a Process of Making the Same, of which the following is a full,clear, and exact description.

I have discovered that refractory bricks, blocks, and other articles ofcarborundum having highly-useful properties can be made by molding intothe form desired what is known in the manufacture of carborundum asamorphous carborundumnamely, an intermediate amorphous condition whichthe carborundum-making ingredients assume in the electric furnace beforetheir final conversion into crystalline carborundum and which 7 is foundin abundance at the end of the run in the outer zone of the furnace. I Itake such amorphous carborundum, compress it into the form desired forthe finished brick or other article, and then place the coherent mass inan electrical furnace and subject it to the high degree of heat requiredin the manufacture of carborundum. The amorphous carborundum is thusconverted into a crystalline mass of carborundum, which is very firm andcoherent, but being considerably more porous than if the brick weremolded from already-crystallized carborundum it is more desirable formany purposes in the artsas, for example intlining furnaces, fire-boxes,&c., for in such uses it will stand sudden changes of temperaturewithout cracking or disintegrating. Other articles in which this porousstructure is of advantage may be made by molding them from the amorphouscarborundum and crystallizing them, as above described.

Where a still more porous article than can be made from amorphouscarborundum is required, I may mold it from a mixture of carbon andsilica in proper proportions to form carbid and then subject it to theheat of the electric furnace in order to convert it into carborundum,which by reason of the original compression of the mixture will be moredense and coherent than carborundum crystals as they exist in theordinary carborundum-furnace, but will be more porous and of less weightper volume than where the article is made of compressed amorphouscarborundum.

Where a degree of porosity between that of an article made of compressedamorphous carborundum and an article made of compressed carborundumcharge mixture is desired, it can be obtained by compounding the articleof amorphous carborundum and charge mixture mixed together.

I may make articles of carbid of boron in the same way by molding themfrom the "amorphous material found in the manufacture of such carbid orby molding them of a mixture of carbon and boracic acid.

The heating of the articles may conveniently be accomplished byembedding them in the charge mixture of an ordinary carborundum-furnace,or they may be treated in a furnace specially constructed for suchpurpose.

Before molding and compressing the amorphous earborundum orcarborundum-forming ingredients I may add to them a solution of silicateof soda or glue or like material, which will act as a temporary bond tohold the article well together before it is heated and crystallized andwhich will be volatilized and dissipated at the high temperature of thefu rnace, or such bond may be omitted altogether and the originalcohesion of the mass obtained only by compressing.

It sometimes happens that the so-called amorphous carborundum islackingin carbon in sufficient proportion to constitute crystallinecarborundum. Such fact in any given case will be recognized by theskilled manufacturer of carborundnm, and suiiicient carbon should thenbe added to make up the deficiency.

My invention is of advantage, because it enables me to make carborundumarticles very cheaply, amorphous carborundum having heretofore been oflittle value, and the articles made therefrom, because of their greaterlightness and porosity, are for many purposes more useful than articlesmade from recrystallized carborundum.

Where for any reason carbon is desired to be incorporated in thearticle, I may add such I00 carbon to the article before it is molded,and where it is present in amount in excess of that required for theformation of the carbid it will remain in the article.

I claim 1. The method herein described which consists in compressinginto coherent form a mass containing non-crystalline material adaptedunder heat to form crystalline carbid, and then crystallizing it bysubjecting it to intense heat; substantially as described.

2. The method herein described which consistsin compressinginto coherentform a body of amorphous carbid and then crystallizingitbysubjectingitto intenseheat; substantially as described.

3. As a new article of manufacture, a coherent crystallized bodycontaining non-crystalline carbid having a porous structure and formedby crystallization of a compressed 20 In testimony whereof Ihavehereunto set 0 my hand.

FRANK J. TONE.

\Vitnesses:

H. M. CORWIN, L. M. REDMAN.

Corrections in Letters Patent No. 709,808.

It is hereby certified that in Letters Patent No. 709,808, grantedSeptember 23,

Frank J. Tone,

d Process of Making Same, errors appear 1902, upon the application of ofNiagara Falls, New York, for an improvement in Oarborundum Articles anon requiring correction, as follows: On page 2, in lines 18 and shouldbe stri in the printed specificati 19, the words substituted, and

containing non-crystalline oken out and the word of in line 21 samepage, the word 01" should be stricken out and the 7 words containingnon-crystalline inserted; and that the said Letters Patent should bethese corrections therein that the same may con read with case in thePatent Office.

Signed and sealed this 18th day of November, A. D., 1902.

F. I. ALLEN,

Commissioner of Patents.

[SEAL] form to the record of the

